Two Democratic candidates for mayor criticized last night a series of labor contracts signed earlier this year by Mayor Marion Barry, saying that provisions in them permitting dues checkoffs to finance union political action committees were an effort by Barry to extract campaign contributions from the unions.

The provisions allow an estimated 10,600 members of the American Federation of Government Employees and the American Federation of State, County and Municipal Employees to contribute part of their biweekly paychecks to the union committees, which in turn contribute to political campaigns.

Both AFGE and AFSCME have endorsed Barry for reelection.

The accusations were made during a combative hour-long debate among the four Democratic mayoral candidates that was broadcast live on WMAL radio.

City Council member John Ray (D-At Large) suggested during the broadcast that the checkoff provisions might have been part of "a sweetheart deal."

"I find it rather peculiar that AFGE, which has never endorsed a candidate [for mayor], and would not endorse Barry even after he won the primary four years ago" has endorsed him this year, Ray said.

Council member Charlene Drew Jarvis (D-Ward 4), also a candidate in the Sept. 14 primary, said, "This is an extraction . . . . It is characteristic of your administration that you have extracted these kinds of contributions."

Barry responded that the agreements were voluntary, progressive and in no way improper.

Donald Weinberg, the city's chief labor negotiator, said earlier this week that the checkoff provisions were approved in July and August. One contract with AFGE involving 600 employes of the Department of Employment Services was approved by him and the department's then-acting director, Ivanhoe Donaldson, he said. Donaldson has since left the department and is now manager of the Barry reelection campaign.

Eleven similar contracts with AFSCME locals involving about 10,000 city employes have also been approved.

Weinberg said the checkoff provisions are under routine review by the Corporation Counsel's Office, and that no deductions are expected to be made for several months.

Throughout the debate -- often punctuated by interruptions from candidates claiming credit for proposals cited by other candidates--Barry's rivals challenged the incumbent's contention that city services have improved since he became mayor in January 1979.

Patricia Roberts Harris, considered Barry's leading opponent in the primary race, quarreled with Barry's assertion that crime has gone down in the city during his administration. Citing statistics to show that the number of robberies, burglaries and homicides had increased, Harris said: "Anyone that wants to call that crime reduction doesn't know the meaning of the word."

The three challengers also contended that the city's credibility on Capitol Hill has eroded during the Barry administration.

"Congress is not clear that we can handle our fiscal affairs," said Jarvis, and therefore, the city has suffered "a loss of respect for our ability to handle our own details."

"The facts are," Barry retorted, "that we have an excellent relationship with Congress. I have demonstrated clearly that we are on the road to recovery."

When Barry cited recent congressional approval of the largest federal payment in the city's history, Ray noted that a House subcommittee has threatened to withhold that payment unless Barry complies with its request to hire 103 more police officers by Sept. 30, the end of the current fiscal year.